You've got to have the right ratio for the track, and Shimano's Dura-Ace cogs come in a range of tooth counts so you can always be prepared. Manufactured from durable chromoly steel, each cog is machined to run perfectly straight.
1.37" x 24 tpi
|13T / 1/8-inch||689228170094||Y27913100||SHI3214461K|
|13T / 3/32-inch||689228170087||Y27913000||SHI33714624K|